Model Specifications	Main technical parameter (50Hz  3φ 380V)					电机型号功率 kW	泵组重量 Kg
	流量 m3/h	扬程 m	转速 r/min	汽蚀余量 NPSHr m	轴功率 kW
11/2BA-6	6	20.3	2900	6.6	0.745	Y90S-2H  1.5	26
	11	17.4		6.7	0.923
	14	14		6.0	1.01
11/2BA-6A	5	16		6.5	0.578
	9.5	14.2		6.9	0.713
	13.5	11.2		6.1	0.825
11/2 BA-6B	4.5	12.8		6.4	0.448	Y802-2H  1.1
	9	11.4		7.0	0.57
	13	8.8		6.3	0.693
2BA-6	10	34.5		8.2	1.87	Y112M-2H  4	43
	20	30.8		7.2	2.62
	30	24		5.7	3.09
2BA-6A	10	28.5		8.2	1.44	Y100L-2H  3
	20	25.2		7.2	2.07
	30	20		5.7	2.55
2BA-6B	10	22		8.2	1.10	Y90L-2H  2.2
	20	18.8		7.2	1.57
	25	16.3		6.6	1.73
2BA-9	11	21		8.0	1.12		38
	20	18.5		6.8	1.47
	25	16		6.0	1.66
2BA-9A	10	16.8		8.1	0.85	Y90L-2H  2.2	38
	17	15		7.3	1.06
	22	13		6.5	1.23
2BA-9B	10	13	2900	8.1	0.70	Y90S-2H  1.5	38
	15	12		7.6	0.82
	20	10.3		9.8	0.91
3BA-6	30	62		7.7	9.3	Y160M2-2H 15	116
	45	57		6.7	11.0
	60	50		5.6	12.3
	70	44.5		4.7	13.3
3BA-6A	30	45		7.5	6.65	Y160M1-2H 11
	40	41.5		7.1	7.38
	50	37		6.4	7.98
	60	30			8.8
3BA-9	30	35.5		7.0	4.66	Y132S2-2H 7.5	60
	45	32.6		5.0	5.56
	55	28.8		3.0	6.32
3BA-9A	25	21.5		7.0	2.83	Y112M-2H 4
	35	19.7		6.4	3.35
	45	17.4		5.0	3.87
3BA-13	32.4	21.5		6.5	2.5		41
	45.0	18.8		5.5	2.88
	52.2	15.6		5.0	2.96
3BA-13A	29.5	17.4		6.0	1.86
	39.6	15.0		5.0	2.02
	48.6	12.0		4.5	2.15
3BA-13B	28	13.5		5.5	1.63	Y90L-2H  2.2
	34.2	12		5.0	1.72
	41.5	9.5		4.0	1.73
4BA-6	65	98		7.1	27.6	Y250M-2H 55	138
	90	91		6.2	32.8
	115	81		5.1	37.1
	135	72.5		4.0	40.4
4BA-6A	65	82		7.1	22.9	Y200L2-2H 37
	85	76		6.4	26.1
	105	69.5		5.5	29.1
	125	61.6		4.6	31.7
4BA-8	70	59		5.0	17.5	Y200L1-2H 30	116
	90	54.2		4.5	19.3
	109	47.8		3.8	20.6
	120	43		3.5	21.4
4BA-8A	70	48		5.0	13.6	Y180M-2H 22
	90	43		4.5	15.3
	109	36.8		3.3	16.8
4BA-12	65	37.7		6.7	9.25	Y160M2-2H 15	108
	90	34.6		5.8	10.8
	120	28		3.3	12.3
4BA-12A	60	31.6		6.9	7.4	Y160M1-2H 11	108
	85	28.6		6.0	8.4
	110	23.3		4.5	9.5
4BA-18	65	22.6			5.32		65
	90	20		5	6.28
	110	17.1			6.93
4BA-18A	60	17.2			3.80	Y132S2-2H 7.5
	80	15.2			4.35
	95	13.2			4.80
4BA-25	54	17.6	2900	5	3.69	Y132S1-2H 5.5	44
	79	14.8			4.10
	99	10			4.02
4BA-25A	50	14			2.80	Y112M-2H 4
	72	11			2.87
	86	8.5			2.78
6BA-8	110	36.5	1450	6.6	15.6	Y200L-4H 30	166
	140	35.9		6.3	18.3
	170	32.5		5.9	19.7
	200	29.2		5.2	21.4
6BA-8A	110	30.5		6.6	12.7	Y180L-4H 22
	140	28.6		6.3	14.8
	170	25.8		5.9	15.7
	200	21.3		5.2	16.7
6BA-8B	110	24.4		6.6	10.2	Y160L-4H 15
	140	22.0		6.3	11.3
	180	18.1		5.9	13.6
6BA-12	110	22.7		8.5	8.96	Y160L-4H 15	146
	160	20.1		7.9	10.8
	200	17.1		7.0	11.8
6BA-12A	95	17.8		8.6	6.18	Y160M-4H 11
	150	15		8	7.69
	180	12.6		7.6	8.07
6BA-18	126	14.3		6.0	6.3	Y132M-4H 7.5	134
	162	12.5		5.5	6.50
	187	9.6		5.0	6.62
6BA-18A	115	11		6.0	4.93
	144	9.5		5.5	5.03
	162	8		5.0	5.18
8BA-12	220	32		6.5	24	Y225S-4H 37	191
	280	29.1		5.6	26.9
	340	25.4		4.7	29.4
8BA-12A	220	26		6.7	17.1	Y200L-4H 30
	250	24		6.1	20.1
	290	21.8		5.5	21.2
8BA-18	220	20		6.2	14.9	Y180L-4H 22	180
	285	18		5.5	16.6
	360	14		5.0	17.5
8BA-18A	220	17.5			11.9	Y160L-4H 15
	260	15.7		5.8	13.3
	320	12.7			13.9
8BA-25	216	14.5		5.5	10.6		143
	270	12.7		5.0	11.3
	324	11.0		4.5	11.8
8BA-25A	191	11.4		5.0	7.68	Y160M-4H 11
	238	9.9		4.5	8.00
	285	8.6		4.0	8.56

How to select a marine horizontal centrifugal pump？

1) Define Operating Conditions (Determine the Pump’s Hydraulic Point)

Application/System: Seawater cooling, freshwater circulation, ballast, bilge, fire fighting, general transport, etc. (Different applications have different requirements for corrosion resistance, self-priming, and specifications).

Flow Rate Q (m³/h): Normal/Maximum/Minimum, whether adjustment is required.

Head H (m): Static head + pipeline friction/local losses + heat exchanger/filter/valve pressure drop + margin.

Medium: Seawater/Freshwater/Oil; Temperature, density, viscosity, presence of sand/impurities/gas.

Selection Goal: To ensure the operating point falls as close as possible to the pump’s Optimal Efficiency Point (BEP) on its curve. Long-term operation is generally recommended within approximately 70%–110% of the BEP flow rate.

2) Suction Conditions and Cavitation (Very Critical for Marine Applications)
Calculate the NPSHa available from the system (determined by liquid level, suction pipe losses, medium temperature/saturated vapor pressure, etc.). To meet the following requirements: NPSHa ≥ NPSHr (as per the sample) + margin (usually 0.5–1 m or as recommended by the classification society/manufacturer).

Suction piping should be as short, straight, and with few bends as possible to minimize suction-side resistance. Appropriately increase the suction inlet diameter to reduce pressure drop caused by filters/seagates. Avoid installing the pump too high, which could lead to suction head conditions (especially since warm water/seawater is more prone to cavitation).

3) Pump structure selection (related to flow rate, head, and maintenance)
Common horizontal centrifugal pump structure selections:

Single-stage end-suction horizontal pump: General-purpose first choice (medium to low head, easy maintenance).

Split-case (double-suction) pump: High flow rate, lower NPSH, easy maintenance (common in fire fighting/ballast).

Multi-stage horizontal pump: High head requirements (e.g., special feedwater/high-pressure delivery).

Self-priming required: Ordinary centrifugal pumps do not self-prime; if air intake or self-priming is possible in bilge/emergency pumping, a self-priming centrifugal pump or a priming device should be selected.

4) Materials and Corrosion Protection (Key Focus for Seawater Pumps)

Seawater: Prioritize aluminum bronze/bronze, duplex stainless steel (e.g., 2205), and seawater-resistant cast iron with a reliable anti-corrosion coating; ensure compatibility with the system metals for galvanic corrosion, and implement sacrificial anode/insulation measures if necessary.

Freshwater: Cast iron/ductile iron with rust prevention or stainless steel.

Sand/Impurities: Wear-resistant materials, replaceable wear rings/wear-resistant rings; reduce speed if necessary.

5) Shaft Seal and Reliability

Mechanical seals are the mainstream: Select friction pairs according to the medium (seawater often uses more wear-resistant and corrosion-resistant combinations); implement flushing/cooling solutions if necessary.

Consider: Whether short-term dry running is permissible (mostly not), seal cavity pressure, and ease of maintenance.

Marine environments experience significant vibration, requiring higher standards for bearings and alignment; base rigidity and installation quality are crucial.

6) Drive and Control (Confirm 50/60Hz Difference)

Electrical System: **Voltage/Frequency (50/60Hz)** determines the speed, affecting the pump’s Q/H/NPSH.

Adjustment Method: Variable frequency speed control is preferred, as it is more energy-efficient and pump-friendly than long-term flow throttling.

Starting Method: For high-power applications, consider soft start/variable frequency conversion, and calculate the impact of starting current on the ship’s network.

7) Classification Society and Standards: Confirm whether type approvals or inspection certificates such as CCS/ABS/DNV/LR are required based on ship requirements.

Fire pumps typically have specifications regarding rated flow, head, emergency power supply/layout, etc., which need to be checked in advance.

8) Maintenance and Spare Parts: Prioritize **back pull-out** structure: Allows for core removal and maintenance without dismantling the piping.

Confirm the supply cycle and universality of vulnerable parts (mechanical seals, bearings, wear rings); ships often use a “one in use, one standby” redundancy system.